L'il Big Haulers engine runs slow

[cwinkler95602]

I got a L'il Big Haulers set for my son about 10 months ago and it worked fine until about a month ago.  Now the engine runs at less than half the speed and has no power when the cars are hooked up. 

I first cleaned the engine wheels and track with a soft cloth and there appears to be minimal crud on both.  Next, I checked the voltage on the track and it varies with the controller setting as would be expected and is about 16V when at the maximum setting. I also took the terminal and applied it directly to the engine wheels and the wheels ran at about the same speed as when on the track.  So there does not appear to be anything wrong with the controller or the track.   

The engine is less than a year old, so it is still under warranty, but before returning it to Bachmann, it would be nice to confirm that this is really a problem with the engine.  Any other thoughts about what this problem is?

thanks in advance.

[grsman]

Where do you have this set up?
You are not running it on the floor on carpet are you?
Tom

[Loco Bill Canelos]

There is not a whole lot that seems to go wrong with them so far.  If not clogged with carpet hair, does it run balky?, or motor runs fast but wheels run slow?  Can you turn the wheels when the motor is off? Is there a chattering noise that might indicate a gear is slipping or stripped?

It could be that the wheels are clean and the track is clean, but the contacts between the motor and wheels are dirty. Looking at the diagram there are brass wipers which carry power from the axles to the motor, It could be as simple as these got corroded or are dirty.  There seems to be four screws that hold the bottom plate so you could try looking at the wipers.

You could try calling the service department for help, before sending it in.  800-356-3910  ext 334 or 335   or call 215-533-1600  and ask for service.

Wish I could help more, and hopefully someone who has one can chime in and help way better than I can.

[cwinkler95602]

I am running it on the floor on carpet.  Why is that a problem?  I don't see any sign of carpet fibers in the wheels.

The motor does not run balky, it's just slow, the motor and the wheels.  I don't smell anything funny either, like a motor that is straining and I don't hear any funny chattering noises like there is a problem with gears.  You cannot move the wheels by hand when the motor is off.

I don't believe there is any problem with the terminals, they look quite clean.

Any ideas?

thanks for the help.

[grsman]

Engines tend to pick up carpet fibers. The fibers get wound around the axels.
They could get in the drive system and bind the drive. Which Lil Big Hauler do you have?
I have a couple and could look at mine and see what might be going on.
You said it has no power when the cars are hooked up. Does the engine run ok without the cars?
If it does, check the wheels on the cars to make sure they are not binding and are free turning.
Tom

[cwinkler95602]

Tom,
The engine runs slow by itself and runs even slower, barely moving, with cars hooked up.  So there is nothing wrong with the cars.

I could open up the motor and see if there are carpet fibers in there.  Seems unlikely as it is a low pile carpet and I would expect to see some fibers sticking out.  But it's something to check.

thanks,
Chris

[cwinkler95602]

I opened up the engine compartment and there is absolutely no carpet fibers in there, so that isn't the problem.

Any other ideas?

thanks.

[Chuck N]

Do you have a multimeter?  If you do, check the voltage on the track when the train is running poorly, at full power.  Take the train off the track and check the voltage on the track at full power.  Is there a switch on the power supply that says something like "G" or "LS"?  If there is make sure it hasn't been switched to a lower voltage option.   Chuck

[cwinkler95602]

Chuck,
The voltage was the first thing I checked and at full throttle it is 16V.  When the train is running it would drop down to 11V which doesn't sound right.

The funny thing is that my son was just messing around with it and it suddenly started working again. Now with the train running properly at full speed, the voltage on the track doesn't drop at all.

At this point, I am thinking that there is a resistive short in the motor that was causing the voltage to drop.  Now somehow that short has cleared itself, at least for now.

thanks,
Chris

[Loco Bill Canelos]

Chris,

It may be as simple as that the loco got bumped while being played with causing poor contact, and got bumped again and is now making good contact.  If it is working leave it be, and be alert when symptoms come back if they come back.   

Looking at the wiring diagram I did notice that the motor does have a noise suppression PCB soldered to the motor so that it meets FCC interference  rules.  Many years ago we had a problem with those PCB boards heating up and causing problems, back then we just removed them from the motor and attached the motor leads directly to the motor.  If you have trouble again use your meter to check the voltage at the wipers, then if no loss in voltage, test at the point the wires attach to the PCB on the motor , and at the point the wires go from the PCB to the motor.  At some point the voltage will drop and you will know where exactly the problem is.  This procedure has never failed me in finding problems with locomotives sent to me for repair, back when I was doing that sort of thing. 
 
Have fun playing with it and with your son!!!

Bill

[cwinkler95602]

Hi Bill,
That is excellent information you have provided.  I bet that there is a cold solder joint on that PCB that you mention and possibly when I opened it up, the wires got bumped a little allowing it to make good contact again.  So likely the joint will fail again soon, but I can track it down as you suggest.

thanks again!

Chris

[NarrowMinded]

Im not sure what gear set up the little big Big hauler has but if it has a worm gear on the on the motor output shaft i would look at the clearances between the gear and the motor if the problem comes back.

Sometimes when a loco with a worm gear is pushed/slid  on the  track it can cause the worm gear to slide on the shaft which may cause the gear to rub or be  misaligned with its mating gear.

The fact that the wheels can't be freely turned makes me believe its a wormgear setup

NM-Jeff